- MAOIs are potentially lethal in overdose and
pose a potential risk for clients with depres-
sion who may be considering suicide.
The SSRIs, first available in 1987 with the re-
lease of fluoxetine (Prozac), have replaced the cyclic
drugs as the first choice in treating depression because
they are equal in efficacy and produce fewer trouble-
some side effects. The SSRIs and clomipramine are
effective in the treatment of OCD as well. Prozac
Weekly is the first and only medication that can be
given once a week as maintenance therapy for de-
pression after the client has been stabilized on fluoxe-
tine. It contains 90 mg of fluoxetine with an enteric
coating that delays release into the bloodstream.
PREFERRED DRUGS FOR CLIENTS
AT HIGH RISK FOR SUICIDE
Suicide is always a primary consideration when treat-
ing clients with depression. SSRIs, venlafaxine, ne-
fazodone, trazodone, and bupropion are often a bet-
ter choice for those who are potentially suicidal or
highly impulsive because they carry no risk of lethal
overdose in contrast to the cyclic compounds and the
MAOIs. Evaluation of the risk for suicide must con-
tinue even after treatment with antidepressants is
initiated. The client may feel more energized but
still have suicidal thoughts, which increases the
likelihood of a suicide attempt. Also, because it often
takes weeks before the medications have a full ther-
apeutic effect, clients may become discouraged and
tire of waiting to feel better, which can result in sui-
cidal behavior.MECHANISM OF ACTION
The precise mechanism by which antidepressants
produce their therapeutic effects is not known, but
much is known about their action on the CNS. The
major interaction is with the monoamine neuro-
transmitter systems in the brain, particularly nor-
epinephrine and serotonin. Both of these neuro-
transmitters are released throughout the brain, and
help to regulate arousal, vigilance, attention, mood,
sensory processing, and appetite. Norepinephrine,
serotonin, and dopamine are removed from the
synapses after release by reuptake into presynaptic
neurons. After reuptake, these three neurotransmit-34 Unit 1 CURRENTTHEORIES ANDPRACTICE
Table 2-5
*mg/day for oral dose
C, capsule; T, tablet; L, liquid; INJ, injection for IM use.
ANTIDEPRESSANTDRUGS
Generic (Trade) Name Forms Usual Daily Dosages* Extreme Dosage Ranges*SELECTIVE SEROTONIN REUPTAKE INHIBITORS
Fluoxetine (Prozac) C, L 20 50–80
Fluvoxamine (Luvox) T 150–200 50–300
Paroxetine (Paxil) T 20 10–50
Sertraline (Zoloft) T 100–150 50–200
Citalopram (Celexa) T, L 20–40 20–60
Escitalopram (Lexapro) T 10–20 5–30
CYCLIC COMPOUNDS
Imipramine (Tofranil) T, C, INJ 150–200 50–300
Desipramine (Norpramin) T, C 150–200 50–300
Amitriptyline (Elavil) T, INJ 150–200 50–300
Nortriptyline (Pamelor) C, L 75–100 25–150
Doxepin (Sinequan) C, L 150–200 25–300
Trimipramine (Surmontil) C 150–200 50–300
Protriptyline (Vivactil) T 15–40 10–60
Maprotiline (Ludiomil) T 100–150 50–200
Mirtazapine (Remeron) T 15–45 15–60
Amoxapine (Ascendin) T 150–200 50–250
Clomipramine (Anafranil) C, INJ 150–200 50–250
OTHER COMPOUNDS
Bupropion (Wellbutrin) T 200–300 100–450
Venlafaxine (Effexor) T, C 75–225 75–375
Trazodone (Desyrel) T 200–300 100–600
Nefazodone (Serzone) T 300–600 100–600
MONOAMINE OXIDASE INHIBITORS
Phenelzine (Nardil) T 45–60 15–90
Tranylcypromine (Parnate) T 30–50 10–90
Isocarboxazid (Marplan) T 20–40 10–60